Wiring power tool batteries in Parallel

[tearlurker]

So I saw this battery on Amazon, it is a 12v 9aH tool battery. I thought if I could wire 4 of these in parallel I could get enough juice for my power needs (fantastic fan, 2 Led lights and an small fan). Any issues I should be aware of ( exploding lithium batteries come to mind). If this works it’s seems like a economical and light weight solution.

https://www.amazon.com/TenMore-Milwaukee-48-11-2401-48-11-2440-48-11-2460/dp/B0785HM6SD?psc=1&SubscriptionId=AKIAILSHYYTFIVPWUY6Q&tag=duckduckgo-ipad-20&linkCode=xm2&camp=2025&creative=165953&creativeASIN=B0785HM6SD

[troubleScottie]

Your solution is: 36 AH. With Li, you can consume down to about 80% of total power (28 AH) to ensure a long life.

Basically you need to compare your power usage against your stored energy.

The LED lights are pretty small usage. One could disregard. Unless they are left on for a long time.

A Fantastic fan uses 1 to 3 AH per hour. If you use your fan for 8 hours a day (while you are in the TD), you consume between 8 and 24 AH. On high, that is basically all your battery in 8 hours.

Your other fan will most likely have similar or worse power consumption.

So at low fan settings, you have 14 hours of battery. At high, about 4.5 hours. One or two days power at most. So no glamping for you. One might be looking for 125AH for a better usage range.


Also you need some method of recharging. Obviously the standard charging bases are the best choice. It is not clear if a solar controller could safely recharge these batteries.


Another issue is connecting to the batteries. One might be able to get a connector that can positively connect to the batteries. As opposed to a more standard Li or lead acid battery post system. You want to maintain the connectors on the batteries for charging.

[John61CT]

The 18-20V types are better for voltage range,

5S vs 3S

Ryobi's latest version, purchase from HD only, good warranty, great deals sometimes free tools.

Just need a DCDC converter to give the right voltage output, e.g. 13.8 and a USB adapter, HowTo's online, not rocket science

Or use 4S LFP chemistry, safer than the other LI types.

[edgeau]

Connecting them can be "interesting". Either you build something they will click into like on a tool or you pull them apart to get the actual cells and wire them up in a new case. I considered the former. There were 3D print files downloadable for the Ryobi ones that could be changed from one to several receptors but in the end I kept it simple and got an AGM battery.

Sent from my Pixel using Tapatalk

[John61CT]

Yes, physical more of a DIY challenge than the electrickery.

Best to keep the modules intact, have internal BMS, the chargers tuned to the modules, including 12V input

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